Speech therapy is the corrective or rehabilitative treatment of physical and/or cognitive deficits/disorders resulting in difficulty with verbal communication. This includes both speech (articulation, intonation, rate, intensity) and language (phonology, morphology, syntax, semantics, pragmatics, both receptive and expressive language, including reading and writing). Depending on the nature and severity of the disorder, common treatments may range from physical strengthening exercises, instructive or repetitive practice and drilling, to the use of audio-visual aids.

Speech and language therapists (SLTs), or Speech-Language Pathologists (SLPs) are allied health professionals. They work with children and adults who have difficulties with communication, or with eating, drinking and swallowing. (However, difficulties with eating and drinking may also fall under the scope of the occupational therapists profession.)

Speech and language therapists work closely with parents and caregivers and other professionals, such as teachers, nurses, occupational therapists and doctors.

Health Services employ most SLTs. Other therapists work for education services or charities. Some therapists work independently and treat patients privately.

Speech and language therapists work in community health centres, hospital wards and outpatient departments, mainstream and special schools, day centres and in their clients' homes. Some now work in courtrooms, prisons and young offenders' institutions.